INDIAN SOILS

INDIAN SOILS

Indian Council of Agricultural Research (ICAR) has divided Indian soils into eight major groups:

They are by far the largest and the most important soil group of India. They are composed of sediments deposited by rivers and the waves. Their chemical composition makes them one of the most fertile in the world. Usually deficient in nitrogen and humus (thus fertilizers are needed).

Occupy the plains (from Punjab to Assam) and also occur in the valleys of Narmada and Tapti in M.P. & Gujarat, Mahanadi in the MP and Orissa, Godavari in A.R and Cauvery in T.N.

Can be divided into Khadar (new) and Bhangar (older, more clayey and kankary) alluvium.

Black Soil in India

• Also called Regur and is ideal for cotton crop. These soils have been formed due to the solidification of lava spread over large areas during volcanic activity in the Deccan Plateau, thousands of years ago.

• They are black due to compounds of iron and aluminium (also because of titaniferous magnetite). Mainly found in Deccan Plateau – Maharashtra, Gujarat, M.P, Karnataka, Andhra Pradesh, and Tamil Nadu.

• Apart from cotton cultivation, these fertile soils are suitable for growing cereals, oilseeds, citrus fruits and vegetables, tobacco and sugarcane.

• They have high moisture retention level.

• Lack in phosphorus, nitrogen and organic matter.

Red Soil in India

• They are mainly formed due to the decomposition of ancient crystalline rocks like granites and gneisses and from rock types rich in minerals such as iron and magnesium. The term ‘red soil’ is due to the wide diffusion of iron oxides through the materials of the soil.

• Covers almost the whole of Tamil Nadu, Karnataka, Andhra Pradesh, S.E. Maharashtra, and Chhattisgarh, parts of Orissa, Jharkhand and Bundelkhand.

• Generally deficient in nitrogen, humus and phosphorus, but rich in potash.

• Suitable for rice, millets, tobacco and vegetables (also groundnuts and potatoes at higher elevations).

Laterite Soil in India

• Found in typical monsoon conditions – under conditions of high temperature and heavy rainfall with alternate wet and dry periods. The alterations of wet and dry season leads to the leaching away of siliceous matter and lime of the rocks and a soil rich in oxides of iron and aluminium compounds is left behind.

• Found in parts of Western Ghats, Eastern Ghats, Rajmahal hills, Maharashtra, Karnataka, Kerala, Orissa, West Bengal, Assam, Tamil Nadu, etc.

• Poor in nitrogen and minerals.

• Best for tea, coffee, rubber, cinchona, coconut and suitable for rice and millet cultivation if manured.

Forest and Mountain Soils

• Such soils are mainly found on the hill slopes covered by forests. The formation of these soils is mainly governed by the characteristic deposition of organic matter derived from forest growth.

• In the Himalayan region, such soils are mainly found in valley basins, depressions and less steeply inclined slopes. Apart from the Himalayan region, the forest soils occur in higher hills in south and the peninsular region.

• Very rich in humus but are deficient in Potash, phosphorous and lime and needs fertilizers.

• Plantation of tea, coffee, spices and tropical fruits.

Arid and Desert Soils

• A large part of the arid and semi-arid region in Rajasthan and adjoining areas of Punjab and Haryana lying between the Indus and the Aravallis receiving less than 50 cm of annual rainfall is affected by desert conditions.

• This area is covered by a mantle of sand which inhibits soil growth.

• The phosphate content of these soils is as high as in normal alluvial soils. Nitrogen is originally low but its deficiency is made up to some extent by the availability of nitrogen in the form of nitrates. Thus the presence of phosphates and nitrates make them fertile soils wherever moisture is available.

• The changes in the cropping pattern in the Indira Gandhi Canal Command Area are a living example of the utility of the desert soils.

Saline and Alkaline Soils

• In the drier parts of Bihar, Up Haryana, Punjab, Rajasthan and Maharashtra, are the salt-impregnated or alkaline soils. Known by different names: Reh, kallar, USAR, etc.

• Some of the salts are transported in solution by the rivers and canals, which percolates in the sub-soils of the plains.

• The accumulation of salts makes the soil infertile and renders it unfit for agriculture.

Peaty and Marshy Soils

• Originate in the humid regions as a result of accumulation of large amounts of organic matter in the soil. They contain considerable amounts of soluble salts and 10 – 40% of organic matter.

• Peaty soils are found in Kottayam and Alappuzha districts of Kerala, where it is called Kari.

• Marshy soils, high in vegetable matter, are found in northern Bihar, coastal parts of Orissa, Tamil Nadu and West Bengal and parts of UP

Soil Erosion in India

• Acute in hilly and dry regions

• Causes – depletion of forests, wrong use of lands such as cultivation on very steep slopes, cattle rearing. It ultimately leads to Badland Topography.

• Remedy – Afforestation, contour cultivation etc.

Soil of India: Types, ph Range and Regional Distribution

Type	Features (formation, composition)	Distribution	Predominant Crops
Alluvial Soil pH range: 6.5-8.4	Two types: Khaddar- light in color, more siliceous in composition and composed of newer deposit Bhaggar- the older alluvium is composed of lime nodules and has clayey composition. It is dark in color.	Ganga and Brahmaputra river valleys ; deltas of Godavari and Krishna ; plains of Uttar Pradesh, Uttaranchal, Punjab, Haryana , West Bengal and Bihar ; Coastal strip of peninsular India	Rice , Wheat, Sugarcane, oilseeds
Desert Soil pH range: 7.6-8.4	Contain a high percentage of soluble salts but are poor in organic matter; rich enough in phosphate though poor in nitrogen	Rajasthan, Northern Gujarat and southern Punjab	Wheat, grams, melon, bajra (with irrigation)
Black Soil pH range: 6.5-8.4	The soils are derived from basalts of Deccan trap. They derive their name from their black color which may be owing to presence of titanium, iron. Consist of calcium and magnesium carbonates; high quantities of iron, aluminum, lime and magnesia and poor percentage of phosphate, nitrogen and organic matter	Maharashtra and Malwa plateaus , Kathiawar peninsula, Telengana and Rayalasema region of Andhra and northern part of Karnataka	Cotton , millets(include Jowar ,Bajra and ragi ), tobacco, sugarcane
Mixed Red and Black Soil pH range: 6.5-7.5		Scattered in Peninsular India	Millets, wheat
Red Soil pH range: below 5.5-7.5	Mainly formed due to decomposition of ancient crystalline rocks like granites and gneisses and from rock type rich in minerals such as iron and magnesium. Generally poor in nitrogen, phosphorus, humus but rich in potash. Siliceous and aluminous in nature. Clay fraction of the red soils generally consists of Kaolinitic minerals.	Eastern parts Deccan plateau, southern states of Kerala , Tamil Nadu and Karnataka and Chota Nagpur plateau (Jharkhand)	Wheat, Rice , Cotton , Sugarcane, pulses
Grey and Brown pH range: 7.6-above 8.5		Semi- arid tract of Rajasthan and Gujarat	Cotton, oilseeds
Laterite Soil pH range: below 5.5	Composed mainly of hydrated oxides of iron and aluminum; loss of silica from the soil profile	Assam hills, hill of summits of Kerala and Karnataka and eastern Ghats region of Orissa	Coffee, rubber, cashew nut, tapioca
Mountain soil pH range: 5.0-6.5		Coniferous forest belt of Jammu and Kashmir, Himachal Pradesh, Uttaranchal and Sikkim	Fruit, tea

Indian Soils with Percentage of Coverage

Soil Types	Percentage of Total Area
Alluvial soils	22.16
Black Soils	29.69
Red and yellow Soils	28.00
Laterite Soils	2.62
Arid Soils	6.13
Saline soils	1.29
Peaty and Organic Soils	2.17
Forest	7.94